Investments and other assets - Components of Investments and Other Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investments, All Other Investments [Abstract]
Cash value life insurance	$ 50,452	$ 51,188
Equity method investments	22,960	27,098
Cost method investments	24,497	17,374
Deferred debt issuance costs	9,350	6,048
Other long-term assets	36,206	35,458
Total	$ 143,465	$ 137,166

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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Amount of investments, and noncurrent assets classified as other.

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Amount of noncurrent assets classified as other.

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